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Bahamas Equipment Test 2023

During the last week of March 2023 five of us (Forrest, Ralph, Mike, my cousin Kevin, and myself) headed over to the Bahamas aboard Forrest’s 2003 Cabo 35 Express. Throughout the eight-day trip, we ran the boat hard through rough seas and calm. My analysis of how the boat, her equipment, and crew fared follows.

We provisioned for all contingencies – enough food for an army, and lots of ice, beer, wine, liquor (rum, of course!), and cigars. We also carried plenty of spare filters and lubricants, impellers, safety gear, and lots of fishing equipment.

Our plan was to motor fast over to Bimini for one night, then head to Great Harbour Cay in the norther Berry Islands the next day. Not everything goes as planned when it comes to boating.

Region of the Bahamas We Fished

Day one: We left the dock in Boca Raton early to try to stay ahead of the rising northeast swell in the Gulf Stream. We were able to maintain 20-22 knots using the Cabo’s Caterpillar 3126B diesel engines running at 2200+/- RPM. We ran southeast toward Bimini taking the seas and wind on the beam, which resulted in a very wet ride over. Thankfully, the Cabo has excellent Exalto pantograph windshield wipers with washers, as well as helm air conditioning! The isinglass enclosure kept us dry. We arrived at the Bimini Big Game Club Marina at around 9:30am local time. After checking in at Customs, we headed out to fish along the ledge of f the west cost of Bimini, and Ralph reeled in a nice mahi.

Forrest Filleting the Mahi with Surgical Precision

Upon heading back in, we checked into the marina and our rooms at Resorts World Bimini, and relaxed on the dock after cleaning up. The rooms are architecturally beautiful, but anyone who has stayed there knows how annoying the lighting controls are! I must say, the resort is starting to appear well-used. The condition of the Hilton shows some decay that has accumulated since our last visit in 2019. We had drinks and appetizers at the Sushi Bar, then went into The Tides restaurant for dinner.

Day two: Our plan to continue on to Great Harbour Cay were spoiled by the continued rough seas, which had swung to the east overnight. Strong east winds had whipped the Northeast Providence Channel into 5-6 foot head seas, and we wanted no part of that! We decided to fish off Bimini for the day. Prior to setting out, our daily engine check revealed a black mess forward between the engines. MY FAULT! I had checked and topped off the oils the day prior, and forgot to install the oil cap on the starboard engine. The small mess demonstrated that the starboard engine has a good set of rings. It also demonstrated that Tim does not perform well at 0600!

Fishing had mixed results. Lots of barracudas! We hooked into one sizable fish (suspected wahoo), that unspooled nearly a whole reel-full of braided line (on a size 30 reel). We are not seasoned sport fishing pros. Advice from some captains says to keep the boat moving so the fish can’t let go. Others say stop the boat and reel like crazy. We opted for the former, and as the spool of line on the reel became smaller, the temptation to increase drag won out. The line parted at the splice between braid and mono. It appears that the splice slipped. Reminded me of a tip from my father, an avid fly-fisherman, to put a dab of nail polish on the splice to keep it from unraveling. We haven’t had a chance to try it yet, as non of the guys on the trip carried a makeup bag. Kevin cooked up the mahi from the day before for an excellent dinner, with leftovers used for superb smoked fish dip.

Day three: We headed out early to make the deep water run around Great Isaac Cay and fish the canyons along the way. The seas had settled some, but not very much from the day prior. We ran hard out of Bimini harbor heading north for about an hour until the seas were too rough to go fast. We trolled instead, hoping for a wahoo for which the area is well known. We trolled straight into the 4-5 foot head seas, and caught nothing but barracudas! After about four hours of trolling, we decided to pull in lines and head southeast in the hopes of finding calmer seas in shallower water to make the next 60 nautical miles before dark. Amazingly, no-one got seasick. We all got a laugh watching Kevin trying to take a nap in the forward berth, only to be thrown in the air over every wave!

We could run at about 18 knots max into the breaking swells, and sometimes had to throttle back to avoid crashing hard off the back of the occasional 6-8 foot wave. It was a very intense slog. I found myself pleased that the Cabo still has Furuno NavNet 3D plotters. The old Furunos are bullet-proof, and the physical buttons proved very useful in the rough seas. I do not recommend tough-screen only installations for any boat that may experience seas of four feet or more. Most modern touchscreen displays are compatible with a keypad input device – a must-have item.

The Cabo is equipped with a Standard Horizon GX2200 VHF with built-in GPS and AIS receiver. This allowed us to hail an oncoming freighter by name, to coordinate passing starboard-to-starboard and avoid confusion. Gotta love AIS!

We found the conditions a bit better in less than 500 feet of water, as the Great Bahama Bank sheltered the area from the larger swells. We were able to increase speed slowly, until we were running at 24-25 knots at 2300 RPM. We made it to the Great Harbour Cay Marina at about 4:30pm exhausted and ready for rum! We rode in our rented Toyota pickup, with Ralph at the wheel (remember to stay on the left!), to the wonderful beachfront home called Casa Marina (rented via VRBO.com). Our hostess, Isabel, left the house nicely decorated and well equipped for a comfortable four-night stay. The views are spectacular!

The View from Casa Marina, Great Harbour Cay, Bahamas

Great Harbour Cay offers an extremely well protected marina, and friendly, helpful people. There is a Customs officer on the island, and he will come to your boat to check you in if needed. A fuel dock with diesel and gasoline is available adjacent to the island’s power generating plant. We found two liquor stores, one with Cuban (maybe) cigars, a small grocery store, and lots of beautiful views.

Day four: Our group decided to fish the deep water of the Northwest Providence Channel to the northeast of Great Harbour Cay, and try out the new dredges to see if we could raise a wahoo. We trolled around between 200 and 800 feet, and caught nothing by barracudas again! The home-made dredge rigs performed well, and were easy to manage. We turned northeast for deeper water to try to get away from these pests, with no luck. Eventually, in about 1400 feet of water, we began to see pings on the Furuno fishfinder at about 300 feet. We also sighted two frigate birds circling and diving for the water, so we felt we would have good luck following the birds. After chasing the frigate birds for an hour we grew weary of or lack of success and trolled toward the route back to the Great Harbour Cay Marina. Just as we were reeling in lines to pack it in for the day, a hard strike hit one of the 50s, and all five of us jumped into action. Kevin worked the reel, with no short supply of advice from backseat fishermen. After about a 20 minute fight, we successfully landed a 45-50 pound wahoo! Kevin, our very own amateur chef, made an awesome sushi dish for dinner that night!

Kevin with the Prize Wahoo

Day five: Our team got off to a casual start at around 11:00am and after buying fuel, motored southwest across the bank headed for “The Pocket,” a narrow chasm between Chub Cay and Andros Island. It was a smooth ride running 22-24 knots at 2200 RPM. The Pocket is a well known fishing spot, and the light southeast breeze on this day made for the best conditions for game fish. As we turned east and passed the channel marker, we knew we were in the right place.

About a half-dozen large sportfishers – Viking, Hatteras, Merritt and others – were trolling at the western lip of the Pocket, all within about two miles of one another. We politely worked our way into the rhythm of the trolling patterns and prepared our gear. Within about ten minutes, we hooked a nice sailfish, and had the attention of all the big rigs! Mike fought with that sailfish for about 30 minutes to land it. After the fight was over and we had safely let the big fish return to the sea, we trolled for about another hour with no luck before packing in and heading back to GHC.

Day six: The crew decided to have a low-key day, so after some local shopping we cruised up to the area northeast of GHC again. Nothing by barracudas again. We still had lots of wahoo left, so we didn’t take it personally. We headed back to Casa Marina to relax with drinks and cigars. This was our last evening at Great Harbour Cay, so we soaked it in.

Day seven: The seas were building again, and it was time to head back to Bimini. We took the same route we used to get to Great Harbour Cay, with the goal of fishing the canyons off Great Isaac Cay again. We found nothing but barracudas again! We pulled in lines and cruised southwest as fast as we could with reasonable comfort. Once we gained shelter off the west coast of Bimini we turned toward the harbor entrance and made full speed. We checked into the Big Game Club Marina for the night. Talking with other people on the docks, we were the only boat that caught anything you could eat! Seems the ‘Cudas were all that were biting. We decided to have dinner upstairs at the Bimini Big Game Bar & Grill to give Chef Kevin a break.

Day eight: Time to head home! After sleeping in late, we discovered that there were several electrical glitches in the DC circuits on the Cabo. The Balmar SG200 Battery Monitor system indicated no faults with the batteries. After some quick troubleshooting and no luck finding the problem, we decided to run on minimal DC loads and deal with the problem back in Florida. It appears that all those waves and heavy spray over the bow have taken a bit of a toll. Curiously, the electrical ghosts cleared up along the way back to Boca Inlet. That was a very good thing! A dredging crew had equipment blocking most of the entrance to the inlet, and I needed the wipers/washers to see clearly to safely helm the boat through the inlet on an outgoing tide with 4 foot following seas that rose to 6 or 8 between the breakwaters. Everyone clenched and held on tight, and we rode the top of a breaking wave all the way in. After breathing a sigh of relief that I didn’t crash Forrest’s pride and joy, we turned for home and contacted US Customs for clearance.

After packing up our gear and cleaning the Cabo, I reflected on how five men from widely varied backgrounds remained on speaking terms for eight days. Our common interest in boating surely helped! The biggest test of all was for the crew, and we all want to do it again.

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Volvo Neutra Salt Real-World Test

We purchased our current Demo Boat in February of 2020 (Just in time for the Pandemic!) and found that the previous owner had no idea what the Neutra Salt system was for. He kept the boat on a lift a good distance up the St Lucie river, so the engines and exhaust were flushed with mostly fresh water. I reconnected the Neutra Salt systems correctly and added the Neutra Salt solution to each tank. I have been using the system every time we return to the dock. I should probably use it when we anchor overnight, but usually forget to do it.

After finding a few broken/missing hose clamps (Can you believe how cheap the OEM ones are??) and some cracking on the exhaust hoses, I decided to replace all the hoses and clamps. The hoses I purchased came with hose clamps (only one at each end) that were lower quality than the OEM clamps. My preference for all hose clamps on a boat are the ABA type that do not have slots that chew up hoses. The ABA clamps I use are made by Scandvik, and have a 7mm hex head worm. I sure wish my 11-in-One screwdrivers had a 7mm nut driver!

For the hose replacement I decided to pull the exhaust elbows off the twin Volvo Penta 8.1 OSi-D engines to make removal and installation easier, and to inspect the cast iron components. The manifolds and elbows were replaced new in early 2019, so they have been dealing with South Florida seawater for three and a half years. They have been regularly treated with NeutraSalt for about two and a half years. Here are photos of how they looked when they came apart:

I think the manifolds and elbows look pretty good for their age and about 200 hours of use. I cleaned them up and touched up the paint, then reinstalled with new gaskets. They should be good for several more years!

Happy Cruising!
Tim Allen

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Freight Forwarders

At Boundless Outfitters, cruisers are our bread and butter. To help other cruisers find economical shipping options to get products to far-away places, we offer this courtesy list of popular freight forwarders.

Here are a few of the most common freight forwarders our customers like to use. We have no affiliation with them, but offer their contact information here as a convenience to our customers. We accept no liability for errors, omissions, or any problems in doing business with them. Use at your own risk.

Double Ace Cargo
Florida, Panama
11027 NW 122nd St
Medley, FL 33178
+1 (305) 805-3555
www.doubleace.net
Four Star Cargo
Florida, Jamaica & Eastern Caribbean
7640 NW 63rd St
Miami, FL 33166
+1 (305) 717-6200
www.4-star.com
Hyde Shipping
Florida, Belize, Cancun, Grand Cayman, Honduras
3740 West 104th Street Suite 1
Hialeah, FL 33018
www.hydeshipping.com
Makers Air
Florida, Bahamas
2331 Northwest 55th Court
Hangar 19 A
Fort Lauderdale, FL 33309
+1 (954) 771-0330
freight@makersair.com
www.makersair.com
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Does Volvo Neutra-Salt Really Work?

The Boundless Outfitters demo boat is a 2007 Regal 3760 Commodore with twin Volvo 8.1 gas engines that are raw water cooled (yikes!). This is considered to be terrible for boats used in brackish and salt water. Our boat came equipped with Volvo’s Neutra-Salt system installed for both engines. The engines are also equipped with fresh water flushing ports.

The Neutra Salt system is basically a tank with a solenoid valve that allows a small amount of the salt neutralizer to flow into the engine’s raw water cooling water system. The salt neutralizer is teed into the cooling hose prior to the raw water pump, so the solution is dispensed throughout the entire engine, manifolds, and risers. The instructions call for actuating the Neutra-Salt system for 45 seconds before turning off the engine. No fresh water flushing is needed.

I have asked engine repair shops about Neutra-Salt, and have not gotten good answers as to how effective the solution is. Neutra-Salt is expensive at over $50/gallon, so it better work! I decided to perform an experiment to determine the effectiveness, and whether another (cheaper) product could be a fair substitute.

Purpose:

To compare effectiveness of Neutra-Salt in brackish water solution and CRC Salt Terminator in brackish water solution, against fresh water flushing or doing nothing at all.

Setup:

Three sealed containers were filled with equal amounts of brackish water drawn from Lake Boca Raton. One sealed container was filled with the same amount of fresh water drawn from the boat’s tank. 

Two teaspoons of Volvo Neutra Salt was added to one container of brackish water.

Two teaspoons of CRC Salt Terminator was added to one container of brackish water.

One short length of one inch square steel tubing was added to each container.

Results:

After 24 hours, the containers were photographed with a flashlight shining to highlight the condition of the steel sample.

After 72 hours, the containers were photographed again in the same manner:

Conclusion:

After three days, Volvo Neutra-Salt solution is the clear winner. The steel sample still looks perfectly rust free. The CRC Salt Terminator is somewhat effective, but not quite as effective as Neutra Salt.

I was surprised to see that the sample in fresh water has almost as much rust as the sample in untreated brackish water. That tells me that fresh water flushing has little effect, and is almost as bad as not flushing at all. 

Recommendation:

Based on this experiment, I strongly recommend the Volvo Neutra Salt system for every gas engine operated in salt water – even those with fresh water cooling. Exhaust manifolds are rarely fresh water cooled on gas engines, and don’t last long (typically 3-5 years). Replacement manifolds,  risers and elbows cost upwards of $2000 or more per engine. Using Neutra-Salt will extend the life of these costly components by a significant amount of time.

Further testing:

So far, this experiment has only been running for three days. I will keep it going for a few weeks and update this page. 

It would be interesting to determine whether using Neutra-Salt in engines that already have some rust will stop the decay. At the conclusion of the test I will move the sample from the untreated brackish water container to the Neutra Salt container to see what happens.

Follow Up:

After one week of soaking steel samples in the various solutions, the only noticeable changes were more oxidation on the three samples that were not in the Neutra Salt solution. Here are the photos:

It is obvious that the Neutra-Salt from Volvo Penta is the clear winner. I am not a chemist, but something significant is happening to protect the steel sample from the ravages of aqueous salt solution.

Additional Test:

To learn how an engine that has already suffered some rust will respond to treatment with Neutra Salt, I moved the steel sample from the untreated brackish sample to the Neutra Salt solution, leaving in place the steel sample that had been there all week. After about 18 hours, I took photos:

I could not believe my eyes! The formerly rusty sample is now clean as a whistle. You can see how the sample that was once rusted has softer edges. I left the raw edges from the cutoff wheel on all the steel samples, as can be seen on the sample at the lower part of the photo. I am truly amazed, and a believer in Volvo Penta’s Neutra Salt!

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Who Needs Compass Binoculars?

by Tim Allen

How many people have passed the binoculars to another person, only to repeatedly say “No, not there – there”?

We have all been there, done that. What a hassle! If you were passing binoculars with a built-in compass, you could tell the other person “Look to 243°,” and they will see exactly what you saw.

Now let’s take the old hand-bearing compass. Hold it at arm’s length at eye level and … you know the story. You focus on the compass dial and can’t see the target you are lining up. Focus on the target and you can’t see the compass dial. Enter the binoculars with the built-in compass. Now you can see the target and compass dial at the same time – clearly.

Compass binoculars are invaluable when sailing without radar, especially at night. A good set of compass binoculars do a great job of gathering light, and the illuminated compass dial allows you to track other vessels accurately.

At sea is not the only place for compass binoculars. Ever go bird watching with friends? Wouldn’t it be great if you could just give the bearing to that rare falcon? Add a rangefinder reading and you can’t miss!

Now that binoculars with a built-in compass are widely available, there is no reason not to have at least one set on board at all times.

Happy cruising!

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Power Tools Off-Grid

Corded or Cordless Tools – Which are Better for Cruising?

Before we went cruising on our catamaran “Unbound,” I shopped around and bought a set of cordless power tools to bring along. I thought this would be the greatest thing since sliced bread. Like many people, I had worked on projects away from convenient power. You know the projects – building the kids’ gym set in the back yard, attaching a bracket to a wall from a ladder, hanging a mirror. Many of us have done these things.

One morning, after a couple weeks aboard “Unbound” I took on the project of mounting a GPS display near the helm. I needed to drill four holes. I grabbed my trusty cordless drill and … it was dead. I plugged it into the charger and turned on the inverter. Fifteen minutes later the inverter control panel was yelling at me (with yellow and red lights) that the batteries were too low! Now to crank up an engine to charge the battery bank, so I can drill four holes.

According to the label on the drill’s one-hour battery charger, it uses 65 watts at 120 VAC. The charger puts out 2 amps at 16 VDC. That’s 32 watts, so the charging efficiency is less than 50%. Our Xantrex inverter/charger is about 90% efficient at supplying 120 VAC, so to charge the drill’s battery for one hour uses about 6 amp-hours of house battery current.

Now let’s look at drilling those holes with a regular, old-fashioned corded drill. My Milwaukee drill (in storage at the time) is rated at 3.5 amps at 120 VAC, under full load. Now, I was drilling fairly small holes through fiberglass, so lets say it would draw 2 amps (240 watts). Each hole took about 15 seconds to drill. That’s one minute at 240 watts, at 90% inverter efficiency – 22.2 amps at 12 VDC. The total battery drain would have been only 0.37 amp-hours! That’s only 6% of the power used for the cordless drill! And, I wouldn’t have had to wait an hour to do the job.

If your getaway plans include a tool kit with cordless power tools – don’t waste your money! Their batteries are almost never charged when you need them, so you have to run your inverter or generator for an hour to charge them up (if you remembered to get the fast charger) before you can get started with your project. A cord-type power tool is ready all the time, and you only need to run your inverter while you are using it. Corded tools also take up less space (no bulky batteries or chargers). Saves time and house battery amps!

True off-grid life is different! Whether on a boat or in an RV, or in a mountain cabin, electricity usage off-grid is totally different. The number three priority for any cruiser (after safety and water) is battery power. Without it we have no communications, navigation, lights – or engines!

Update:

Battery technology for power tools is constantly changing. The latest Lithium Ion batteries hold their charge for a very long time. With this in mind, cordless tools get a second chance on board. I love the power and consistent tool speed that the new batteries offer. However, I don’t like the surprise when the battery is discharged – the tool just stops without warning!

The charging efficiency of Lithium Ion batteries is similar to the NiCd battery example above. If you are seriously pinching amp-hours, you may still want to use your corded tools.

Happy Cruising!

Tim Allen

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Vented Loops Help Prevent Your Boat from Sinking

As you already know, Vented Loops are an integral part of any plumbing system that uses a thru-hull connection below the waterline, and has the potential for siphoning water into the boat.

The most common application of a vented loop I have seen is in the black water discharge for holding tank pump-outs. We all know that you should NEVER pump your holding tank into inland lakes or waterways. That would be disgusting! Take your boat out past the 3-mile limit before pumping. Some engine exhaust systems also employ vented loops.

Other applications for vented loops, less commonly installed, are engines and generators mounted low in the boat. Many installers don’t even give it a second thought – they install the engine or generator with the factory plumbing. Engines and generators come from the factory with the raw water pump outlet going directly to the heat exchanger using a short, often pre-molded, hose. Please don’t trust this setup if your engine or generator will be mounted near or below the waterline.

Recently a service client of Boundless Outfitters experienced a boaters worst nightmare – his sailboat sank at the dock, right behind his house! Now, he is not blind, nor inattentive – he just doesn’t use the boat much. The boat didn’t hit bottom. I say it “sank” because it flooded with raw water beyond the capacity of the bilge pumps (more on that later). Fortunately, our client saw the boat riding low on her waterline and investigated. He immediately installed a portable sump pump to remove the excess water and bring the boat back to her proper waterline. Then he called us to investigate the cause.

What I found was surprising. The entire interior of the boat was coated in black goo up to about one foot above the cabin sole. It took a while to determine what the mess consisted of. I set about looking into all bilges looking for water flowing into the hull. I found nothing! I then looked at the main engine (a turbocharged Yanmar, 4JH4-TE, installed as a re-power) and found water dripping from the air intake screen near the turbocharger. At first I thought maybe the water accumulated in the air intake when the water level rose, and was still dripping. So I pulled the screen off, and saw that the water was still coming from the crankcase vent hose! Drip-drip-drip. This can’t be good!

As it turns out, raw water had found its way past the raw water pump impeller and filled the water-lift muffler. It then proceeded to fill the engine through the open exhaust valves. (By the way, this is why you don’t keep cranking your engine if it fails to start – the muffler fills with water!) This particular boat is a center-cockpit ketch, with the engine below the cockpit sole, very low in the boat. Too low, as it turns out.

After filling the engine with raw water, the overflow ran into the bilge. This should have been no problem for the bilge pumps to keep up with – it was just dripping quickly as far as I know. Now it occurred to me what the black goo was – ENGINE OIL! Engine oil, being less dense than water, floats. When the engine began to fill with raw water, the oil was the first thing to overflow. Turns out bilge pumps hate engine oil. They failed. Now it was just a matter of time before the boat began to fill with raw water, carrying that slick of black, gooey engine oil on top, coating everything that got wet with a film of used engine oil. This was a total mess. Not to mention the damage to the engine from being filled with salt water for such a long time.

Root cause: The engine is installed completely below the waterline. This engine, that was installed brand new about five years ago, used the factory hose between the raw water pump and heat exchanger. The installer did not consider the consequences of water getting past the pump with the engine stopped. The water did not siphon into the engine, it just slowly filled because it was below the waterline.

Lesson learned: Install a vented loop! The loop needs to be in the portion of the system that gets pressurized when the system is operating. It cannot be installed in the suction side of a pump, as it will do its job and let air in. The hose connecting the water pump to the heat exchanger on a main engine or generator must be extended to a vented loop well above the waterline. Optionally, a vented loop can be installed after the heat exchanger if there is a hose between the heat exchanger and the exhaust elbow. Check your engine installations to see if the raw water pump and heat exchanger are near the waterline. If they are, install a vented loop downstream of the pump. If you can’t install a vented loop where needed, close the seacock every time you moor, and place the engine key near the valve handle as a reminder.

You, or a professional technician, should review all your boat’s plumbing installations on a regular basis. Inspect for worn, kinked or cracked hoses, rusted hose clamps, leaks and so on. Make sure all hoses are the proper type for the application. Exercise all your seacocks at least twice per year. If any appear questionable, replace them at your next haul-out. Don’t forget about your fresh water plumbing. That is a subject for another article…

Happy cruising,
Tim

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Crevice Corrosion Can Ruin Your Watermaker!

You may have heard of Crevice Corrosion. Perhaps you  have confused it with galvanic corrosion (electrolysis), but the chemical process is quite different.

Without explaining all the chemistry (as some of it is beyond my Chemistry 201 studies!), I will explain what happens. Essentially, Crevice Corrosion occurs to Stainless Steels when in the presence of seawater that has been depleted of oxygen. How does this happen?

Seawater that is trapped against stainless steel equipment loses its oxygen over time by causing oxidation of the materials it is in contact with. Crevice corrosion does not require dissimilar metals to occur. In fact, it can even occur where a plastic part is clamped to a stainless steel part (or even painted stainless steel!), if seawater is allowed to become trapped between the parts.

The result looks a lot like galvanic corrosion, but is not caused by the same problems.

Common boating equipment that frequently suffers from crevice corrosion is trim tabs. I have seen trim tabs that have been properly maintained, with zincs replaced regularly, fall prey to crevice corrosion. This usually occurs between the hydraulic ram base and the tab itself. You should inspect yours, and always make sure that the components of your trim tabs are well bedded in a waterproof compound (3M 4200 or 5200 or similar adhesive). Don’t trust silicone for this critical task.

Another piece of equipment that we see suffering from crevice corrosion is your watermaker high-pressure pump and high-pressure fittings. This is due to inadequate fresh water flushing of your desalinator. Would you believe that some watermaker manufacturers still build systems with no easy method for fresh water flushing?

The potential for crevice corrosion is why I personally prefer Titanium Alloy or Nickel Aluminum Bronze (NAB) for high pressure watermaker pumps.

To learn more about crevice corrosion, please see this Wikipedia article on crevice corrosion.

Happy cruising!
Tim